plastic

Nolan Miller butterfly brooch featuring pink plastic and clear rhinestones
Photo courtesy of Scott Papper, GIA GG, AJP, CM (NAJA), Global Gemology & Appraisals
Species:  Plastic
​​Mohs Hardness:  3 to 4 out of 10
Color:  Can be any color.
RI:  1.460 to 1.700
Birefringence:  None
SR/DR/AGG:  SR, commonly with strong ADR due to strain
Spectrum:  Not diagnostic
Fluorescence:  Not diagnostic
SG:  1.05 to 1.55

plastic facts


Plastic used to be the standard material for watch crystals, even for luxury brands like Rolex.

Plastic can be produced in nearly all colors.

Plastic has a very light heft.

Colorful plastic molds are used in costume jewelry pieces, as they are able to be mass produced quickly, and cost-efficiently.
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